This is only my opinion of what I would do if I were financing a home. It is only an opinion and cannot be guaranteed to be in the best interest of any or all other borrowers.

Interest rates are based on numerous economic, financial and credit based factors that adjust daily. In addition, lenders can vary on the qualification requirements from mortgage program to mortgage program. If you like the rate today, then the safe bet is to lock in. Even if rates improve, most likely they won't improve enough in the short term to make you cry about it. But if you are an ardent market bear and believe that we'll keep hearing more bad economic for a while, and you have the money to risk, then you may benefit from floating. Just remember, it always seems more painful to have not locked when you should have as opposed to locking in now and watching rates get a little better.